1.3 Bonding

Question 1

Metalic bond

Answer 1

Attraction between positive metal ions and delocalised electrons

Question 2

Ionic bond

Answer 2

Electrostatic attraction between oppositely charged ions

Question 3

Which elements do not form ions?

Answer 3

Boron
Carbon (usually)
Silicon (usually)

Question 4

What ions does tin form?

Answer 4

Sn⁴⁺ (most stable) and Sn²⁺

Question 5

What ions does lead form?

Answer 5

Mostly Pb²⁺ but some Pb⁴⁺

Question 6

Covalent bond

Answer 6

A shared pair of electrons

Question 7

What is a lone pair?

Answer 7

A pair of electrons which are not bonded

Question 8

What are non-octet molecules?

Answer 8

Molecules where the central atom does not have a noble gas electron arrangement

Question 9

Coordinate bond

Answer 9

A covalent bond in which both electrons of the shared pair come from the same atom

Question 10

How does a lone pair effect the bond angle?

Answer 10

Reduces angle by 2.5 degrees

Question 11

Electronegativity

Answer 11

The power of an atom to attract the pair of electrons in a covalent bond

Question 12

Most electronegative atom

Answer 12

Fluorine

Question 13

Why does electronegativity increase across a period?

Answer 13

The number of protons (nuclear charge) increases

Question 14

Why does electronegativity decrease down a group?

Answer 14

Atomic radius increases as the number of shells increases

Question 15

Why don’t the noble gasses have electronegativity values?

Answer 15

They do not usually form covalent bonds

Question 16

Three types of intermolecular force

Answer 16

• van der Waals’s forces
• Permanent dipole-dipole forces
• Hydrogen bonds

Question 17

Electron deficient

Answer 17

Where the central atom of a non-octet molecule has fewer electrons than the noble gas configuration

Question 18

Expanded octet

Answer 18

Where the central atom of a non-octet molecule has more electrons than the noble gas configuration

Question 19

Shape:
2 bond pairs
0 lone pairs

Answer 19

Linear
(180°)

Question 20

Shape and angle:
3 bond pairs
0 lone pairs

Answer 20

Trigonal planar
(120°)

Question 21

Shape and angle:
4 bond pairs
0 lone pairs

Answer 21

Tetrahedral
(109.5°)

Question 22

Shape and angle:
5 bond pairs
0 lone pairs

Answer 22

Trigonal bipyramidal
(90° and 120°)

Question 23

Shape and angle:
6 bond pairs
0 lone pairs

Answer 23

Octohedral
(90°)

Question 24

Shape and angle:
2 bond pairs
1 lone pairs

Answer 24

V-shaped
(117.5°)

Question 25

Shape and angle:
3 bond pairs
1 lone pairs

Answer 25

Trigonal pyramidal
(107°)

Question 26

Shape and angle:
2 bond pairs
2 lone pairs

Answer 26

V-shaped
(104.5°)

Question 27

Shape and angle:
3 bond pairs
2 lone pairs

Answer 27

Trigonal planar
(120°)

Question 28

Shape and angle:
4 bond pairs
2 lone pairs

Answer 28

Square planar
(90°)

Question 29

van der Waals’ forces

Answer 29

• Movement of electrons unbalances charge distributions creating an instantiations dipole.
• This induces a dipole in the neighbouring molecules

Question 30

Effect of Mr on strength of van der Waals’ forces

Answer 30

Larger molecules have more electrons so there are larger induced dipoles, so forces are stronger.

Question 31

Permanent dipole-dipole forces

Answer 31

• Positive and negative ends of neighbouring molecules are attracted to each other
• Occur in addition to van der Waals’ forces

Question 32

Hydrogen bonding

Answer 32

• Forms between positive H atom and the lone pair of the neighbouring molecule
• Occur in addition to van der Waals’ forces

Question 33

Which atoms can hydrogen bond with for hydrogen bonds to form between molecules?

Answer 33

Nitrogen
Oxygen
Fluorine
(Most electronegative atoms)

Question 34

Properties of substances with hydrogen bonding

Answer 34

• Higher boiling points than other substances with similar Mrs
• Usually dissolve in water (forms hydrogen bonds with water)

Question 35

What is needed for a substance to dissolve?

Answer 35

Attraction between solute and solvent molecules

Question 36

What do ionic and polar substances dissolve in?

Answer 36

Polar solvents

Question 37

What do non-polar substances dissolve in?

Answer 37

Non-polar solvents

Question 38

Why are metals malleable and ductile?

Answer 38

Layers of ions in the giant metallic lattice can slide over each other without disrupting the metallic bond

Question 39

Why are ionic substances brittle?

Answer 39

If layers in a giant ionic lattice slide over each other, they cause like charges to line up, the repulsion causes the structure to break down.